Toolholder assemblies of the so-called "wedge clamping" or "spring clamping" types are employed for single point operations, for example, grooving and parting off, during which time the inclined front end of a holder blade's upper clamping jaw positioned to the rear of a cutting insert's front cutting edge is subject to considerable abrasive wear by chips curling up thereagainst. Such wear poses a considerable danger both to an operator and the tool environment by virtue of the fact that the snapping off of an upper clamping jaw's front portion acting to retain a cutting insert would catapult it and the hitherto retained cutting insert at substantially the peripheral velocity of a rotating workpiece. In view of this danger, for the purpose of safety, holder blades are replaced at relatively frequent intervals which could otherwise be considerably extended were the abrasive wear of their upper clamping jaw's front end be inhibited.
One approach employed to extend the working life of a holder blade is to braze a wear resistant shield onto its upper clamping jaw's front end, the wear resistant shield being made of a suitable material considerably harder than the holder blade's base metal. However, this approach suffers from the disadvantage that the replacement of a worn shield is a relatively cumbersome process which can be itself injurious to a holder blade when not performed under highly rigorous conditions.